LIGHT MY BRICKS LEGO Mercedes Benz Arocs 42043 Lighting Kit, Installation Instructions Manual, Page: 6 / 64

2.) Starting with the left side of the truck, carefully split the section as
per below by creating a gap in between sections, then take a White
15cm Bit Light and thread the connector side of the cable through the
gap we have created.
Thread the cable all the way through until the LED component is up
against the edge on the left of the black stud. Reconnect the following
LEGO section ensuring the Bit Light is right up against Trans Orange Plate,
then reconnect sections to close up the gap and secure the light in place.